ODIER 12.2mm bike trailer hitch coupler for Instep and Schwinn bike trailer allows you to attache an Instep or Schwinn kids/pet bicycle trailer to almost any bike. Easy to Install: Just need 1 minute to install it on a quick-release axle bike, thru axle bike may need adapter. Safe and Comfort: With an additional coupler attachment, 2 bikers can tow the trailer in turn and don't need to exchange the bikes. We all know it's uncomfortably to ride a unsuitable size bike. Strong safety strap: After years of usage, the original strap will become weak, if it Looks worn or aged then you should replace it Package Include: 1 Lock Pin, 1 Coupler, 1 Lock washer, a safety strap